The present invention provides a method for producing a rare earth activated, alkaline earth metal fluorohalide photostimulable phosphor which is expressed by a basic composition formula (Ba1−aMIIa)F(Br1−bIb):zLn, the method comprising the steps of: calcining a precursor of the rare earth activated, alkaline earth metal fluorohalide photostimulable phosphor to obtain a calcined product; and annealing the calcined product so that the following annealing conditions are met: (1) Tmp−600° C.≦Ta≦Tmp−300° C., wherein Ta is the annealing temperature (° C.), and Tmp is the melting point (° C.) of a host crystal; and (2) 10−5≦N×ta≦1, wherein ta is the processing time (in minutes), and N is the number of oxygen moles/the number of phosphor moles.